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基于欧式距离法或因子化法的近红外光谱技术对牛肉掺假鉴定的研究 被引量:9
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作者 陈迎丽 何钰 +3 位作者 龚会琴 赵亚洲 何伟 何智宇 《食品研究与开发》 CAS 北大核心 2019年第15期141-146,共6页
利用近红外光谱技术结合欧氏距离法或因子化法建立牛肉中掺入猪肉和鸡肉的快速、准确的技术方法,从而为保证牛肉制品品质和安全提供强有力的检测手段;以牛肉和掺假肉(掺入猪肉和鸡肉)按照相同程度进行均匀搅碎,按照掺假肉10%为梯度增量... 利用近红外光谱技术结合欧氏距离法或因子化法建立牛肉中掺入猪肉和鸡肉的快速、准确的技术方法,从而为保证牛肉制品品质和安全提供强有力的检测手段;以牛肉和掺假肉(掺入猪肉和鸡肉)按照相同程度进行均匀搅碎,按照掺假肉10%为梯度增量进行制备掺假肉,共分为10类样本(10%至100%),采用单通道,光谱范围为12000cm^-1~4000cm^-1,扫描次数为64次,特征波段为7351.92cm^-1~6824.83cm^-1、5578.24cm^-1~5075.21cm^-1,预处理方式为一阶导数或二阶导数+矢量归一化+9点平滑,结果表明:猪肉和鸡肉掺假因子化法的判别率分别为94%和96.67%;因子化法可以试现对牛肉掺假进行定性分析鉴定。 展开更多
关键词 牛肉掺假 近红外 欧氏距离 因子化法 定性分析
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基于近红外光谱技术对小麦中毒死蜱农药残留测定方法的研究 被引量:9
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作者 冯镇 刘馨 +6 位作者 张震 任双鹤 郭增旺 郭亚男 殷东 郭丽媛 王中江 《食品工业科技》 CAS 北大核心 2022年第4期271-277,共7页
研究了基于近红外光谱技术结合化学计量法建立小麦中毒死蜱农药残留鉴定模型。采用喷洒法制备具有不同毒死蜱残留量的小麦样品,采集样品的近红外漫反射光谱,并建立因子化法、欧氏距离法的定性预测模型和偏最小二乘法的定量预测模型。结... 研究了基于近红外光谱技术结合化学计量法建立小麦中毒死蜱农药残留鉴定模型。采用喷洒法制备具有不同毒死蜱残留量的小麦样品,采集样品的近红外漫反射光谱,并建立因子化法、欧氏距离法的定性预测模型和偏最小二乘法的定量预测模型。结果表明:因子化法较欧氏距离法的定性判别率更高,构建条件的特征波段为5543.68~4643.72、7582.43~6510.28 cm^(−1),预处理方式为二阶导数+矢量归一化+5点平滑,判别率可达96%;偏最小二乘定量判别模型构建条件的特征波段范围为5543.68~4643.72、7582.43~6510.28 cm^(−1),预处理方式为消除常数偏移量,主成分数为7,交叉验证系数(R^(2))达到99.46、交叉验证均方残差(RMSECV)达到1.15,实际值与预测值相关性良好,最低检测限为1 mg/kg,能够实现对小麦毒死蜱农药残留量的准确判定。以上结果表明,利用因子化法建立的定性分析模型的判别率高达96%,能够实现对小麦毒死蜱农药残留的定性分析鉴定,采用偏最小二乘法可以实现定量分析鉴定且重现性较好。 展开更多
关键词 近红外光谱 小麦 毒死蜱 欧式距离 因子化法 偏最小二乘
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State of health prediction for lithium-ion batteries based on ensemble Gaussian process regression
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作者 HUI Zhouli WANG Ruijie +1 位作者 FENG Nana YANG Ming 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期397-407,共11页
The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators ... The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators and ensemble Gaussian process regression(EGPR)to predict the SOH of LIBs.Firstly,the degradation process of an LIB is analyzed through indirect health indicators(HIs)derived from voltage and temperature during discharge.Next,the parameters in the EGPR model are optimized using the gannet optimization algorithm(GOA),and the EGPR is employed to estimate the SOH of LIBs.Finally,the proposed model is tested under various experimental scenarios and compared with other machine learning models.The effectiveness of EGPR model is demonstrated using the National Aeronautics and Space Administration(NASA)LIB.The root mean square error(RMSE)is maintained within 0.20%,and the mean absolute error(MAE)is below 0.16%,illustrating the proposed approach’s excellent predictive accuracy and wide applicability. 展开更多
关键词 lithium-ion batteryies(LIBs) ensemble Gaussian process regression(EGPR) state of health(SOH) health indicators(HIs) gannet optimization algorithm(GOA)
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基于近红外光谱技术对多年际建三江、五常大米产地溯源 被引量:27
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作者 钱丽丽 宋雪健 +3 位作者 张东杰 张丽媛 阮长青 鹿保鑫 《食品科学》 EI CAS CSCD 北大核心 2018年第16期321-327,共7页
研究多年际地理标志大米产地溯源判别技术,保护地理标志大米的品牌效益。利用近红外漫反射光谱技术对试验田样品进行与产地有关的特征波段筛选,并在其范围内对2013—2015年来自建三江地区及五常地区的291份大米样品进行产地溯源研究。... 研究多年际地理标志大米产地溯源判别技术,保护地理标志大米的品牌效益。利用近红外漫反射光谱技术对试验田样品进行与产地有关的特征波段筛选,并在其范围内对2013—2015年来自建三江地区及五常地区的291份大米样品进行产地溯源研究。结果表明,试验田样品在波段为5 136~5 501 cm^(-1)范围内产地因素差异显著。在此范围内利用因子化法建立的定性分析模型及聚类分析模型对建三江大米及五常大米的正确判别率均高于97.00%。利用偏最小二乘法建立的定量分析模对两地区大米的正确判别率分别为95.83%、94.00%。因此,应用该技术对多年份大米的产地溯源进行判别具有一定的可行性。 展开更多
关键词 大米 产地溯源 近红外漫反射光谱技术 因子化法 偏最小二乘
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近红外漫反射光谱技术对小米产地溯源的研究 被引量:18
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作者 宋雪健 钱丽丽 +3 位作者 周义 于果 于金池 张东杰 《食品研究与开发》 CAS 北大核心 2017年第11期134-139,共6页
为建立小米产地溯源的快速检测技术,更好的维护地方名优小米品牌效益,试验利用近红外漫反射光谱技术对不同状态小米进行产地溯源鉴别,试验分别选取来自肇源和肇州两个小米主产区的144份小米样品,应用近红外漫反射光谱技术结合化学计量... 为建立小米产地溯源的快速检测技术,更好的维护地方名优小米品牌效益,试验利用近红外漫反射光谱技术对不同状态小米进行产地溯源鉴别,试验分别选取来自肇源和肇州两个小米主产区的144份小米样品,应用近红外漫反射光谱技术结合化学计量学对不同状态下的小米进行产地溯源研究,结果表明:在全波长范围内采用因子化法建立的定性分析模型和在特征波段范围内采用偏最小二乘法(PLS)建立的定量分析模型,对肇源、肇州两个小米主产区的小米籽粒和小米粉末的正确鉴别率均在90%以上,其中小米粉末的模型正确预测率要高于小米籽粒。因此,应用近红外漫反射光谱技术对不同状态小米产地溯源的鉴别具有一定的可行性。 展开更多
关键词 近红外漫反射光谱技术 小米 因子化法 偏最小二乘(PLS) 产地溯源
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Non-isothermal thermal decomposition kinetics of high iron gibbsite ore based on Popescu method 被引量:2
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作者 柳政根 王峥 +2 位作者 唐珏 王宏涛 龙红明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2415-2421,共7页
The thermal decomposition kinetics of high iron gibbsite ore was investigated under non-isothermal conditions.Popescu method was applied to analyzing the thermal decomposition mechanism.The results show that the most ... The thermal decomposition kinetics of high iron gibbsite ore was investigated under non-isothermal conditions.Popescu method was applied to analyzing the thermal decomposition mechanism.The results show that the most probable thermal decomposition mechanism is the three-dimensional diffusion model of Jander equation,and the mechanism code is D3.The activation energy and pre-exponential factor for thermal decomposition of high iron gibbsite ore calculated by the Popescu method are 75.36 kJ/mol and 1.51×10-5 s-(-1),respectively.The correctness of the obtained mechanism function is validated by the activation energy acquired by the iso-conversional method.Popescu method is a rational and reliable method for the analysis of the thermal decomposition mechanism of high iron gibbsite ore. 展开更多
关键词 high iron gibbsite ore thermal decomposition kinetics activation energy pre-exponential factor Popescu method
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Multiobjective particle swarm inversion algorithm for two-dimensional magnetic data 被引量:8
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作者 熊杰 张涛 《Applied Geophysics》 SCIE CSCD 2015年第2期127-136,273,共11页
Regularization inversion uses constraints and a regularization factor to solve ill- posed inversion problems in geophysics. The choice of the regularization factor and of the initial model is critical in regularizatio... Regularization inversion uses constraints and a regularization factor to solve ill- posed inversion problems in geophysics. The choice of the regularization factor and of the initial model is critical in regularization inversion. To deal with these problems, we propose a multiobjective particle swarm inversion (MOPSOI) algorithm to simultaneously minimize the data misfit and model constraints, and obtain a multiobjective inversion solution set without the gradient information of the objective function and the regularization factor. We then choose the optimum solution from the solution set based on the trade-off between data misfit and constraints that substitute for the regularization factor. The inversion of synthetic two-dimensional magnetic data suggests that the MOPSOI algorithm can obtain as many feasible solutions as possible; thus, deeper insights of the inversion process can be gained and more reasonable solutions can be obtained by balancing the data misfit and constraints. The proposed MOPSOI algorithm can deal with the problems of choosing the right regularization factor and the initial model. 展开更多
关键词 multiobjective inversion particle swarm optimization regularization factor global search magnetic data
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Nuclear factor kappa B: A marker of chemotherapy for human stage Ⅳ gastric carcinoma 被引量:18
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作者 Sheng Ye You-Ming Long +1 位作者 Jian Rong Wen-Rui Xie 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第30期4739-4744,共6页
AIM: To detect the nuclear factor kappa B (NF-κB) condition in human stage IV gastric carcinoma patients and to explore the correlation between NF-κB activation and survival of these patients after chemotherapy. ... AIM: To detect the nuclear factor kappa B (NF-κB) condition in human stage IV gastric carcinoma patients and to explore the correlation between NF-κB activation and survival of these patients after chemotherapy. METHODS: Expression of NF-κB-p65 was determined by immunohistochemical analysis. Activity of NF-κB DNA-binding in carcinoma tissue was detected by electrophoretic mobility shift assay. Kaplan-Meier survival analysis was performed to show the relation between NF-κB and progression-free survival (PFS) or overall survival (OS) of the patients. RESULTS: The positive expression rate of NF-κB-p65 in 60 gastric cancer tissue samples was 76.7% (46160). The expression of NF-κB-p65 was reduced in adjacent carcinoma and normal tissue samples. Electrophoretic mobility shift assay (EMSA) analysis showed a strong activation of NF-κB in cancer tissue samples. A survival difference was found in NF-κB-p65 positive and negative patients. NF-κB-p65 expression was negative in cancer tissue samples (n = 14). PFS was 191.40 ± 59.88 d and 152.93 ±16.99 d, respectively, in patients with positive NF-κB-p65 expression (n = 46) (P = 0.4028). The survival time of patients with negative and positive NF-κB-p65 expression was 425.16 ±61.61 d and 418.85 ±42.98 d, respectively (P = 0.7303). Kaplan-Meier analysis showed no significant difference in PFS or OS. The 46 patient tissue which positive NF-κB-p65 expression was found in the tissue samples from the 46 patients whose PFS and OS were 564.89 ± 75.94 d and s 352.37 ±41.32 d, respectively (P = 0.0165). CONCLUSION: NF-κB is activated in gastric carcinoma tissue, which is related to the OS after chemotherapy. 展开更多
关键词 Gastric carcinoma Nuclear factor kappa B ACTIVATION Survival analysis THERAPY
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Paclitaxel induces apoptosis in human gastric carcinoma cells 被引量:17
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作者 Hai-Bo Zhou Ju-Ren Zhu Department Of Gastroenterology, Shandong Provincial Hospital, Jinan 250052, Shandong Province, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第3期442-445,共4页
AIM;To investigate the apoptosis in gastric cancer cells induced by paclitaxel,and the relation between this apoptosis and expression of Bcl-2 and Bax. METHODS:In in vitro experiments,MTT assay was used to determine t... AIM;To investigate the apoptosis in gastric cancer cells induced by paclitaxel,and the relation between this apoptosis and expression of Bcl-2 and Bax. METHODS:In in vitro experiments,MTT assay was used to determine the cell growth inhibitory rate.Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of gastric cancer cell line SGC-7901 before and after the paclitaxel treatment.Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2 and Bax. RESULTS:Paclitaxel inhibited the growth of gastric cancer cell line SGC-7901 in a dose-and time-dependent manner. Paclitaxel induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics,including morphological changes of chromatin condensation,chromatin crescent formation,nucleus fragmentation and apoptotic body formation.Paclitaxel could reduce the expression of apoptosis-regulated gene Bcl-2,and improve the expression of apoptosis-regulated gene Bax. CONCLUSION:Paclitaxel is able to induce the apoptosis in gastric cancer.This apoptosis may be mediated by down- expression of apoptosis-regulated gene Bcl-2 and up- expression of apoptosis-regulated gene Bax. 展开更多
关键词 Antineoplastic Agents Phytogenic APOPTOSIS CARCINOMA Humans PACLITAXEL Proto-Oncogene Proteins Proto-Oncogene Proteins c-bcl-2 Stomach Neoplasms Tumor Cells Cultured bcl-2-Associated X Protein
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Side Effects during Treatment of Advanced Gastric Carcinoma by Chemotherapy Combined with CIK-cell Transfusion in Elderly People 被引量:10
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作者 Jingting Jiang Changping Wu +6 位作者 Liangrong Shi Ning Xu Haifeng Deng Mingyang Lu Mei Ji Hbei Zhu Xueguang Zhang 《Chinese Journal of Clinical Oncology》 CSCD 2008年第2期79-82,共4页
OBJECTIVE To study the side effects and therapeutic results of autologous cytokine-induced killer (CIK) cell treatment in elderly patients with advanced gastric cancer. METHODS CIK cells were induced and cultured us... OBJECTIVE To study the side effects and therapeutic results of autologous cytokine-induced killer (CIK) cell treatment in elderly patients with advanced gastric cancer. METHODS CIK cells were induced and cultured using biotechnics in vitro, and then the cells were infused back into the patients. Sixty elderly gastric cancer patients treated by chemotherapy (FOLFOX4 protocol) were followed-up. Among them, 29 patients were treated with CIK cells during application of chemotherapy. Short-term curative effects and adverse events from the CIK transfusion and chemotherapy were observed. RESULTS Eight cases developed partial remission (PR), 9 cases moderate remission (MR), 7 cases stable disease (SD) and 5 cases progressive disease (PD). Out of a total of 29 patients who received chemotherapy combined with autologous CIK therapy, the total remission rate (PR + MR) was 58.6%. The total remission rate following chemotherapy alone was 45.2%, including 5 PR cases, 9 MR cases, 7 SD cases, and 10 PD cases. There was a relatively lower rate of severe chemotherapic toxicities in the CIK-cell transfusion group. Side effects of autologous CIK transfusion included chills (13 cases), fever (9 cases), nausea and vomiting (1 case) and general malaise (3 cases). Side effects were treated with conventional therapy resulting in their amelioration. No patients developed shock, blood capillary leakage syndrome, or abnormalities in routine blood, urine, liver and renal function tests.CONCLUSION Adoptive immunotherapy with autologous CIK cells may decrease the clinical signs and symptoms of elderly patients who suffer from advanced gastric cancer. Adverse reactions of patients can be alleviated by conventional therapy. Autologous CIK-cell transfusion may improve endurance to chemotherapy. 展开更多
关键词 gastric carcinoma cytokine-induced killer cells IMMUNOTHERAPY ADOPTIVE side effects.
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False Human Immunodeficiency Virus Test Results Associated with Rheumatoid Factors in Rheumatoid Arthritis 被引量:7
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作者 Yun-chun Li Fan Yang +3 位作者 Xiao-yun Ji Zhong-jun Fang Jun Liu Yue Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2014年第2期103-106,共4页
Objective To investigate if immunological factors associated with rheumatoid arthritis(RA) affect the result of human immunodeficiency virus(HIV) screening by electrochemiluminescence immunoassay(ECLIA) and enzyme-lin... Objective To investigate if immunological factors associated with rheumatoid arthritis(RA) affect the result of human immunodeficiency virus(HIV) screening by electrochemiluminescence immunoassay(ECLIA) and enzyme-linked immunosorbent assay(ELISA). Methods 100 RA cases were enrolled from January 2012 to February 2013 into this study. HIV screening was conducted with ECLIA detecting both HIV-1 p24 antigen, HIV-1 and HIV-2 antibodies, with ELISA and colloidal gold method detecting HIV-1 and HIV-2 antibodies. The samples producing positive results were submitted to the Center for Disease Control for confirmation using Western blotting method. The antibody titers of rheumatoid factors(RF) including RF-IgG, RF-IgM, RF-IgA, and CCP-IgG were analyzed by ELISA. Results The HIV positive-rate determined by ECLIA was significantly higher than that by ELISA and colloidal gold method(P<0.01). The false-positive rate of HIV screening was associated with antibody titers of RF-IgG, RF-IgM, RF-IgA, and CCP-IgG in RA(P<0.01). Conclusion Immunological factors, including RF and anti-CCP antibody, may influence the screening of HIV by ECLIA, producing false-positive result. 展开更多
关键词 human immunodeficiency virus false positive rheumatoid arthritis ANTIBODY
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Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer 被引量:24
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作者 Bin Du Zhen-Yu Yang +5 位作者 Xue-Yun Zhon Mao Fang Yong-Rong Yan Guo-Long Qi Yun-Long Pan Xu-Long Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第9期1219-1226,共8页
AIM:To study the correlation between high metastasisassociated protein 1(MTA1)expression and lymphangiogenesis in colorectal cancer(CRC)and its role in production of vascular endothelial growth factor-C(VEGF-C). METHO... AIM:To study the correlation between high metastasisassociated protein 1(MTA1)expression and lymphangiogenesis in colorectal cancer(CRC)and its role in production of vascular endothelial growth factor-C(VEGF-C). METHODS:Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovasculardensity(LVD,D2-40-immunolabeled)in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting,respectively,with a stable expression vector or siRNA. RESULTS:The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages(P<0.05).Additionally,high MTA1 expression level was correlated with a large tumor size(P< 0.05).A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells(r=0.371, P<0.05).Similar to the VEGF-C expression level,high MTA1 expression level was correlated with high LVD in CRC(P<0.05).Furthermore,over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels,whereas siRNAs-knocked down MTA1 decreased the VEGF-C expression level. CONCLUSION:MTA1,as a regulator of tumor-associated lymphangiogenesis,promotes lymphangiogenesis in CRC by mediating the VEGF-C expression. 展开更多
关键词 Metastasis-associated protein 1 Vascular endothelial growth factor-C LYMPHANGIOGENESIS Colorectal cancer
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Determination of platelet-activating factor by reverse phase high-performance liquid chromatography and its application in viral hepatitis 被引量:1
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作者 Hong-Cui Cao, Xiao-Ming Chen, Wei Xu, Department of Infectious Diseases, First Affiliated Hospital, Medical School of Zhejiang University Key Laboratory of Infectious Diseases of Ministry of Public Health, Hangzhou 310003, Zhejiang Province, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第46期7364-7367,共4页
AIM: To detect the plateletoactivating factor (PAF) and the plasma or serum levels of tumor necrosis factoroa (TNF-α) malondialdehyde (MDA), endotoxin (ET) and to discuss their significance in various types ... AIM: To detect the plateletoactivating factor (PAF) and the plasma or serum levels of tumor necrosis factoroa (TNF-α) malondialdehyde (MDA), endotoxin (ET) and to discuss their significance in various types of viral hepatitis. METHODS: PAF, TNF-α, MDA, and ET levels in 60 controls, 16 cases of acute viral hepatitis, 71 cases of chronic viral hepatitis, 19 cases of severe viral hepatitis were detected by reverse phase high-performance liquid chromatography (rHPLC), bio-assay, ELISA, thiobarbituric acid (TBA), and limulus lysate test (LLT), respectively. RESULTS: The rHPLC was more sensitive and specific than bio-assay (r = 0.912, P〈0.01). The plasma levels of PAF, TNF-α, MDA, and ET in patients with viral hepatitis were higher than those in controls (P〈0.01). CONCLUSION: rHPLC is more reliable and accurate for the detection of PAF. 展开更多
关键词 Platelet-activating factor MALONDIALDEHYDE ENDOTOXIN rHPLC Viral hepatitis
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电力系统潮流并行算法的研究进展 被引量:41
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作者 薛巍 舒继武 +1 位作者 王心丰 郑纬民 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2002年第9期1192-1195,1198,共5页
随着高性价比可扩展集群并行系统的逐步成熟和应用 ,大规模电力系统潮流并行计算和分布式仿真成为可能。该文首先简要介绍了电力系统的潮流计算模型及基本算法 ,分析了算法中存在的困难。然后分析了 4类较重要的电力系统潮流并行算法 :... 随着高性价比可扩展集群并行系统的逐步成熟和应用 ,大规模电力系统潮流并行计算和分布式仿真成为可能。该文首先简要介绍了电力系统的潮流计算模型及基本算法 ,分析了算法中存在的困难。然后分析了 4类较重要的电力系统潮流并行算法 :分块法、多重因子化法、稀疏矢量法和逆矩阵法 ,同时讨论了这 4种潮流并行算法的基本原理和实用效果 ,比较了各种并行算法的优点和局限性 ,并指出基于集群系统的粗粒度区域分解潮流并行算法最具发展潜力。 展开更多
关键词 研究进展 潮流并行算 大型稀疏线性方程组 电力系统 分块 逆矩阵 多重因子化法 稀疏矢量
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An FPGA-based LDPC decoder with optimized scale factor of NMS decoding algorithm
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作者 LI Jinming ZHAGN Pingping +1 位作者 WANG Lanzhu WANG Guodong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第4期398-406,共9页
Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm wi... Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm with variable scale factor is proposed for the near-earth space LDPC codes(8177,7154)in the consultative committee for space data systems(CCSDS)standard.The shift characteristics of field programmable gate array(FPGA)is used to optimize the quantization data of check nodes,and finally the function of LDPC decoder is realized.The simulation and experimental results show that the designed FPGA-based LDPC decoder adopts the scaling factor in the NMS decoding algorithm to improve the decoding performance,simplify the hardware structure,accelerate the convergence speed and improve the error correction ability. 展开更多
关键词 LDPC code NMS decoding algorithm variable scale factor QUANTIZATION
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Landslide initiation and runout susceptibility modeling in the context of hill cutting and rapid urbanization: a combined approach of weights of evidence and spatial multicriteria 被引量:5
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作者 RAHMAN Md.Shahinoor AHMED Bayes DI Liping 《Journal of Mountain Science》 SCIE CSCD 2017年第10期1919-1937,共19页
Rainfall induced landslides are a common threat to the communities living on dangerous hillslopes in Chittagong Metropolitan Area, Bangladesh. Extreme population pressure, indiscriminate hill cutting, increased precip... Rainfall induced landslides are a common threat to the communities living on dangerous hillslopes in Chittagong Metropolitan Area, Bangladesh. Extreme population pressure, indiscriminate hill cutting, increased precipitation events due to global warming and associated unplanned urbanization in the hills are exaggerating landslide events. The aim of this article is to prepare a scientifically accurate landslide susceptibility map by combining landslide initiation and runout maps. Land cover, slope, soil permeability, surface geology, precipitation, aspect, and distance to hill cut, road cut, drainage and stream network factor maps were selected by conditional independence test. The locations of 56 landslides were collected by field surveying. A weight of evidence(Wo E) method was applied to calculate the positive(presence of landslides) and negative(absence of landslides) factor weights. A combination of analytical hierarchical process(AHP) and fuzzymembership standardization(weighs from 0 to 1) was applied for performing a spatial multi-criteria evaluation. Expert opinion guided the decision rule for AHP. The Flow-R tool that allows modeling landslide runout from the initiation sources was applied. The flow direction was calculated using the modified Holmgren's algorithm. The AHP landslide initiation and runout susceptibility maps were used to prepare a combined landslide susceptibility map. The relative operating characteristic curve was used for model validation purpose. The accuracy of Wo E, AHP, and combined susceptibility map was calculated 96%, 97%, and 98%, respectively. 展开更多
关键词 Landslide susceptibility Landslide runout GIS Remote sensing Weights of evidence(Wo E) Analytical hierarchical process(AHP) Relative operating characteristic(ROC) Bangladesh
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Changes of Dry-wet Climate in the Dry Season in Yunnan(1961-2007) 被引量:1
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作者 Zhongyan Huang 《Advances in Climate Change Research》 SCIE 2011年第1期49-54,共6页
Factor analysis was used to investigate the changes of dry-wet climate in the dry season in Yunnan during 1961-2007 based on observed data from 15 stations.Three common factors were extracted from the 9 climatic facto... Factor analysis was used to investigate the changes of dry-wet climate in the dry season in Yunnan during 1961-2007 based on observed data from 15 stations.Three common factors were extracted from the 9 climatic factors.The results showed that the dry-wet climate has evidently changed since the early 1960s.The general trends in the changes of drywet climate were described as slight decrease in humidity and gradual enhancement in drought intensity.The climate during 1960s-1980s was under weak-medium drought.But since early 1990s,dry conditions have markedly strengthened and continued due to uneven temporal distribution of rainfall and climate warming. 展开更多
关键词 dry-wet climate factor analysis dry season YUNNAN
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The expression of HIF-1α and VEGF as well as their correlation with angiogenesis in esophageal squamous cell carcinomas 被引量:2
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作者 Feng Liu Xiaolong Yang +2 位作者 Boying Ding Gang Ren Rongfu Gong 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第4期199-202,共4页
Objective: To investigate the correlations among the expressions of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial cell growth factor (VEGF) and microvessel density (MVD), and their relationships ... Objective: To investigate the correlations among the expressions of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial cell growth factor (VEGF) and microvessel density (MVD), and their relationships to the clinicopathologic characteristics of esophageal squamous cell carcinomas (ESCC). Methods: The expressions of HIF-1α, VEGF and MVD were detected by immunohistochemical method in 45 cases of ESCC, 30 intraepithelial neoplasia and 35 normal esophageal mucosal epithelia tissues. The correlations among the expressions of HIF-1α, VEGF and MVD, and their relationships to the clinicopathologic features of ESCC were analyzed. Results: The rate of positive expression of HIF-1α and VEGF which were 80% and 84% in ESCC were significantly higher than those in intraepithelial neoplasia and normal esophageal mucosal epithelium tissues (P 〈 0.01) and so did the MVD value which was71.10 ±15.02 in ESCC (P 〈 0.01). The expression of HIF-1α and VEGF were positively correlated with the depth of tumor invasion, lymph node metastasis and TNM staging of ESCC. The expressions of HIF-1α were positively correlated with the expressions of VEGF and the value of MVD. Conclusion: Overexpression of HIF-1α is found in ESCC. HIF-1α may induce the angiogenesis in ESCC by upregulating the transcription of VEGF gene. It may play an important role in the carcinogenesis and aggression in ESCC, HIF-1α, VEGF and MVD may be a useful marker for evaluating the biological behaviors of ESCC. 展开更多
关键词 esophageal squamous cell carcinomas hypoxia inducible factor 1 vascular endothelial growth factor mi- crovessel density
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Expressions of Livin and IGF-Ⅱ in colorectal carcinoma and their relationship 被引量:1
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作者 Guanming Bao Changwu Zhang Gexin Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第8期470-474,共5页
Objective: The aim of the study was to test the expressions of Livin and insulin-like growth factor II (IGF-II) in colorectal cancers and discuss their significance of carcinogenesis and progression in colorectal c... Objective: The aim of the study was to test the expressions of Livin and insulin-like growth factor II (IGF-II) in colorectal cancers and discuss their significance of carcinogenesis and progression in colorectal cancers, to provide a new target and theory basement for cancer therapy. Methods: The expressions of Livin and IGF-II were detected by immuno- histochemistry SABC in 60 cases of colorectal cancer and their associated colorectal tissues, and the associations between the expression levels of Livin and IGF-II and clinical pathological characteristics were analyzed. Results: The positive rates of Livin and IGF-II in colorectal carcinomas were 68.33% and 63.33% respectively, higher than those of para-carcinomatous normal tissues and colorectal adenomas. There were no significant correlations between the expressions of Livin, IGF-II in colorectal carcinomas and the patient's age, sex, tumor size and location, while distant metastasis, Dukes stage, histologi- cal type, lymph node metastasis, and whether the tumors have received radiotherapy and chemotherapy were significantly correlated with the expressions of Livin, IGF-II in colorectal carcinomas. Conclusion: Livin and IGF-II play important roles in carcinogenesis and progression of colorectal cancer. This study showed obvious correlation between the expressions of Livin and IGF-II in colorectal cancers. It could be used as the reference for further researches. Livin is hopeful to be a new molecular target in cancer therapy. 展开更多
关键词 colorectal cancer LIVIN insulin-like growth factor II (IGF-II) IMMUNOHISTOCHEMISTRY
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Expression of VEGF-C and b-FGF in Lung Cancer and Its Relationship with Cancer Progress
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作者 Liu Yan Ma WenHao Ji Liang 《International English Education Research》 2014年第2期78-81,共4页
Objective: to observe expression of vascular endothelial growth factor-C (VEGF-C) and alkaline fibroblast growth factor (b-FGF) in tissues of lung cancer, and its relationship with cancer metastasis.Methods: to ... Objective: to observe expression of vascular endothelial growth factor-C (VEGF-C) and alkaline fibroblast growth factor (b-FGF) in tissues of lung cancer, and its relationship with cancer metastasis.Methods: to adopt immunohistochemical methods, analysis of 60 cases of lung tissue expression of VEGF-C and b-FGF in the situation.Result: positive rates of VEGF-C and b-FGF in lung cancer are respectively 56.67% and 63.33%; expression of VEGF-C and b-FGF in lung cancer is not related to pathological grades, pathologic stages or ages of patients (P 〉 0.05),but closely related to TNM stages and existence of lymph node metastasis (P 〈 0.01). IMVD in center of lung cancer tissues is obviously higher than surrounding area, with significant differences (P 〈 0.01). Conclusion: expression of VEGF-C and b-FGF is related to lung cancer progress. 展开更多
关键词 VEGF-C B-FGF lung cancer progress.
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